252 research outputs found
Resistance Breeding in Apple at Dresden-Pillnitz
Resistance breeding in apple has a long tradition at the Institute of Fruit Breeding now Julius Kuehn-institute in Dresden-Pillnitz. The breeding was aimed at the production of multiple resistance cultivars to allow a more sustainable and environmentally friendly production of apple. In the last decades a series of resistant cultivars (Re®-cultivars) bred in Dresden-Pillnitz has been released, ‘Recolor’ and ‘Rekarda’ in 2006. The main topic in the resistance breeding programme was scab resistance and the donor of scab resistance in most cultivars was Malus x floribunda 821. Due to the development of strains that are able to overcome resistance genes inherited by M. x floribunda 821 and due to the fact that single resistance genes can be broken easily, pyramiding of resistance genes is necessary. Besides scab, fire blight and powdery mildew are the main disease for which a pyramiding of genes is aspired in Pillnitz. Biotechnical approaches are necessary for the early detection of pyramided resistance genes in breeding clones. This paper will give an overview of the resistance breeding of apple in Pillnitz and the methods used
The psychology of esports: a systematic literature review
Recently, the skill involved in playing and mastering video games has led to the professionalization of the activity in the form of 'esports' (electronic sports). The aim of the present paper was to review the main topics of psychological interest about esports and then to examine the similarities of esports to professional and problem gambling. As a result of a systematic literature search, eight studies were identified that had investigated three topics: (i) the process of becoming an esport player, (ii) the characteristics of esport players such as mental skills and motivations, and (iii) the motivations of esport spectators. These findings draw attention to the new research field of professional video game playing and provides some preliminary insight into the psychology of esports players. The paper also examines the similarities between esport players and professional gamblers (and more specifically poker players). It is suggested that future research should focus on esport players' psychological vulnerability because some studies have begun to investigate the difference between problematic and professional gambling and this might provide insights into whether the playing of esports could also be potentially problematic for some players
On Generalizations of Network Design Problems with Degree Bounds
Iterative rounding and relaxation have arguably become the method of choice
in dealing with unconstrained and constrained network design problems. In this
paper we extend the scope of the iterative relaxation method in two directions:
(1) by handling more complex degree constraints in the minimum spanning tree
problem (namely, laminar crossing spanning tree), and (2) by incorporating
`degree bounds' in other combinatorial optimization problems such as matroid
intersection and lattice polyhedra. We give new or improved approximation
algorithms, hardness results, and integrality gaps for these problems.Comment: v2, 24 pages, 4 figure
Maximal height statistics for 1/f^alpha signals
Numerical and analytical results are presented for the maximal relative
height distribution of stationary periodic Gaussian signals (one dimensional
interfaces) displaying a 1/f^alpha power spectrum. For 0<alpha<1 (regime of
decaying correlations), we observe that the mathematically established limiting
distribution (Fisher-Tippett-Gumbel distribution) is approached extremely
slowly as the sample size increases. The convergence is rapid for alpha>1
(regime of strong correlations) and a highly accurate picture gallery of
distribution functions can be constructed numerically. Analytical results can
be obtained in the limit alpha -> infinity and, for large alpha, by
perturbation expansion. Furthermore, using path integral techniques we derive a
trace formula for the distribution function, valid for alpha=2n even integer.
From the latter we extract the small argument asymptote of the distribution
function whose analytic continuation to arbitrary alpha > 1 is found to be in
agreement with simulations. Comparison of the extreme and roughness statistics
of the interfaces reveals similarities in both the small and large argument
asymptotes of the distribution functions.Comment: 17 pages, 8 figures, RevTex
Opposite subduction polarity in adjacent plate segments
Active and fossil subduction systems consisting of two adjacent plates with opposite retreating directions occur in several areas on Earth, as the Mediterranean or Western Pacific. The goal of this work is to better understand the first-order plate dynamics of these systems using the results of experimental models. The laboratory model is composed of two separate plates made of silicon putty representing the lithosphere, on top of a tank filled with glucose syrup representing the mantle. The set of experiments is designed to test the influence of the width of plates and the initial separation between them on the resulting trench velocities, deformation of plates, and mantle flow. Results show that the mantle flow induced by both plates is asymmetric relative to the axis of each plate causing a progressive merging of the toroidal cells that prevents a steady state phase of the subduction process and generates a net outward drag perpendicular to the plates. Trench velocities increase when trenches approach each other and decrease when they separate after their intersection. The trench curvature of both plates increases linearly with time during the entire evolution of the process regardless their width and initial separation. The interaction between the return flows associated with each retreating plate, particularly in the interplate region, is stronger for near plate configurations and correlates with variations of rollback velocities. We propose that the inferred first-order dynamics of the presented analog models can provide relevant clues to understand natural complex subduction systemsPeer ReviewedPostprint (published version
Evaluation of Hungarian Wines for Resveratrol by Overpressured Layer Chromatography
A method, including solid phase extraction sample preparation, overpressured layer chromatographic separation and subsequent densitometric evaluation, was developed for measurement of total resveratrol (cis- and trans-isomers) content of wine. The amount of resveratrol was determined in wine samples from different winemaking regions of Hungary. The total resveratrol was high in Hungarian red wines (3.6–11 mg/L), and much lower in white ones (0.04–1.5 mg/L)
Policy responses to problematic video game use: a systematic review of current measures and future possibilities
Background and aims: Empirical research into problematic video game playing suggests that overuse might cause functional and psychological impairments for a minority of gamers. Therefore, the need for regulation in the case of video games (whether governmental or self-imposed) has arisen but has only been implemented in a few countries around the world, and predominantly in Asia. This paper provides a systematic review of current and potential policies addressing problematic gaming.
Methods: After conducting a systematic search in the areas of prevention, treatment, and policy measures relating to problematic Internet and video game use, papers were selected that targeted problematic gaming policies (N = 12; six in English and six in Korean). These papers served as the basis of this review.
Results: Policies were classified into three major groups: (i) policy measures limiting availability of video games (e.g., shutdown policy, fatigue system, and parental controls), (ii) measures aiming to reduce risk and harm (e.g., warning messages), and (iii) measures taken to provide help services for gamers. Beyond the attempt to classify the current and potential policy measures, the authors also tried to evaluate their efficiency theoretically and (if data were available) empirically.
Discussion and conclusions: Overall, it appears that although several steps have been taken to address problematic video game playing, most of these steps were not as effective as expected, or had not been evaluated empirically for efficacy. The reason for this may lie in the fact that the policies outlined only addressed or influenced specific aspects of the problem instead of using a more integrative approach
Nitrogén-monoxid, neuropeptidek és más nem-adrenerg, nem-cholinerg átvivőanyagok szerepe zsigeri funkciókban, gyógyszeres befolyásolásuk ép és gyulladásos körülmények közt = Role of nitric oxide, neuropeptides and other non-adrenergic, non-cholinergic mediators in visceral functions; their modulation by drugs under normal and inflammatory conditions
A vállalt munka fő céljai: Izolált szervi kísérletekben megismerni a zsigerek mozgásválaszainak mechanizmusait, az állatokon kapott eredményeket humán preparátumokkal összevetve. Szenzoros és más eredetű nem-adrenerg, nem-kolinerg (NANC) transzmitterek azonosítása (funkcionális vizsgálatok és a transzmitter-felszabadulás mérése). Kóros zsigeri működések modellezése. (Egyes irányokban komplett, másokban tájékozódó kísérletek). Közölt eredmények: Új humán adatok közlése mellett összefoglaltuk a kapszaicin zsigeri hatásaival, transzmittereivel kapcsolatos jelentősebb eredményeket. Alappal fölvetettük annak lehetőségét, hogy emberben?és bizonyos állatfajokban is?az NO szenzoros transzmitter (Barthó et al. 2004?Eur J Pharmac; Benkó et al. 2005?Life Sci). Mind állati, mind (világelsőként) humán GI preparátumokban bizonyítottuk az ATP közvetítő szerepét NANC válaszokban (Undi et al. 2005?Bas Clin Pharmac; 2006?Brain Res Bull; Benkó et al 2006?NS Arch Pharmac, 2007?Neurosci). Nem találtunk bizonyítékot VIP szerepére emberi bél kapszaicinnel kiváltott gátló válaszában, a CO szerepére perisztaltikus reflexben (kongresszusi közlés), ill a CO szerepére a NANC gátló válaszban állati és humán GI preparátumokon (ld. fenti közlemények). Közlésre vár: P-anyag és CGRP-IR felszabadulás bélből; szenzoros izgató mustárolaj és H2S hatásmechanizmusa; a passzív szenzibilizáció/antigén-expozíció hatásainak elemzése állati és emberi GI és légúti simaizomzaton stb. | Aims of the project Experiments on isolated tissues for elucidating the mechanisms behind some evoked movements of viscera of animals and man. Identifying sensory and other non-adrenergic, non-cholinergic (NANC) transmitters. Measuring neurotransmitter release. Modelling pathophysiological processes of viscera. (Planned were complete series of experiments in some and pilot experiments in other directions.) Published results Review, containing original results, on visceral effects of capsaicin and the transmitters thereof. Providing indirect evidence that NO is a sensory neurotransmitter (Bartho et al. 2004?Eur J Pharmac; Benko et al. 2005?Life Sci). Proving the presence of purinergic innervation of human (Undi et al. 2006?Brain Res Bull; Benko et al. 2007?Neurosci) and rat intestine (Benko et al. 2006?NS Arch Pharmac). No evidence for a mediating role of VIP in the inhibitory effect of capsaicin in the human gut, a role of CO in the peristaltic reflex (congress presentations) or in the evoked NANC relaxation in animal or human GI preparations (papers as above). To be published Release of substance P- or CGRP-like IR from the gut; mechanisms of action of the sensory stimulants mustard oil and H2S; effects of passive sensitization/antigen exposure on GI and respiratory smooth muscles of animals and man, etc
Wave activity in the neighborhood of the bowshock of Mars
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95091/1/grl4815.pd
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